128 THE ROSE FAMILY. 



Carpels few, on a minute dry receptacle . . . POTENTILLA SIBBALPI. 

 Carpels numerous, on a small, flat, dry receptacle ... 7. POTENTILLA. 

 Carpels numerous, on a large, succulent receptacle ... 6. FRAQARIA. 



Herbs, calyx- tube dry, small, enclosing 1 or 2 carpels 15 



Trees or shrubs, calyx-tube succulent or fleshy, at least when in fruit . . 16 

 ( No petals, calyx-tube smooth 7. 



15 Petals 5, calyx-tube covered with hooked bristles, forming a burr 



( 11. AGRIMONIA. 



( Fruit enclosing from 1 to 5 cells, or hard nuts, arranged round the central 



16 \ axis, each with 1 or 2 seeds . . . 17 



( Fruit enclosing several hairy, seed-like carpels, irregularly placed 12. ROSA. 



{Cells of the fruit closely connate, of a cartilaginous or leathery texture 13. PYRUS. 

 Cells of the fruit closely connate, of a hard, bony consistence . 14. CRAT^EGUS. 

 Cells of the fruit forming distinct bony nuts, but adhering to the inside of the 

 calyx 15. COTONKASTER. 

 Cells bony, somewhat exposed at the top of the fruit, readily separable from 

 each other 16. MESPILUS. 



These Genera are usually distributed into three tribes, considered by 

 some botanists as distinct Orders, viz. : 



1. AMTGDALE^!. Calyx deciduous. Carpel 1, free. Genus: 1. PRUNUS. 



2. RoSE-as. Calyx persistent. Carpels 1 or more, free (but sometimes included 

 in the closed calyx). Genera: -2. SPIR^JA; 3. DRY AS; 4. GEDM; 5. RUBUS; 6. 

 FRAGARIA; 7. POTENTILLA; 8. SIBBALDIA; 9. ALCHEMILLA; 10. SANGUISORBA; 11. 

 POTERIDM ; 12. AGRIMONIA ; 13. ROSA. 



3. POMACES. Calyx persistent, adherent to the ovary, the carpels of which are 

 united, at least in the ripe fruit Genera: It. PYRUS; 15. CRAT.EGUS; 16. COTO- 

 N EASTER; 17. MESPILUS. 



The double-flowering Kerria japonica, so frequently to be met with trained upon 

 cottage garden-walls, formerly supposed to be a species of Corchorus, is now known 

 to belong to the Rosacece. 



1. PRUNUS. PRUNUS. 



Shrubs or trees, with undivided, toothed leaves, and small, free 

 stipules, often scarcely visible ; the flowers either in small bunches on 

 a former year's wood, or in racemes in the axils of young leaves. Calyx 

 free, 5-lobed. Petals 5. Stamens numerous. Ovary of 1 carpel, con- 

 taining 2 pendulous ovules. Fruit a fleshy or juicy drupe, with a hard 

 stone, smooth or rugged, but not wrinkled on the surface, containing 1, 

 or rarely 2 seeds. 



A considerable genus, distributed over the whole of the northern 

 hemisphere, and even abundant within the tropics, both in the New 

 and the Old World, but not extending into the south temperate zone. 

 It is the only British genus with a stone fruit. 



Flowers in axillary racemes 8. P. Padus. 



Flowers solitary or clustered, from leafless buds. 



Flowers single or two together, on short pedicels . . . . 1. P. communis. 



Flowers in clusters, on pedicels longer than the flower itself . 2. P. Cerasus. 



The well-known common Laurel and Portugal Laurel of our gardeners 

 are species of Prunus ( P. Lauro-cerasus and P. lusitantcus), and have no 

 affinity with the true Laurel of the ancients, which is our Bay -tree 

 (Laurus nobilis). The Mahaleb (P. Mahalcb) and the P. semperflorens, 

 both from the continent of Europe, are also frequently to be met with 

 in our shrubberies. The Apricot is another Prunus (P. armeniaca) ; the 

 Almond, the Peach, and the Nectarine belong to the genus Amygdalus, 

 only differing from Prunus in the wrinkled surface of the stone. 



1. P. spinosa, Linn. (fig. 298). Mackthorn, Sloe. In the common, 

 truly wild state, this is a much branched shrub, the smaller branches 

 often ending in a stout thorn. Leaves ovate or oblong, stalked, and 



